7MVA ETO Light NPC converter for multi-MW direct-driven wind turbine application

Direct-driven wind turbine with a PM generator and a full-scale converter is considered to be a preferred solution for wind power generation, especially for offshore application. As the power ratings of wind turbines increase to MW level, medium voltage converter becomes more competitive. The emitter turn-off (ETO) thyristor is a novel semiconductor device that is suitable for high power applications. This paper proposes a 7MVA ETO Light neutral-point-clamped (NPC) converter as the utility interface for direct-driven large wind turbine application. The converter hardware configuration, the component selection and design are presented. The thermal characteristics and performance of the proposed converter are analyzed in detail.